Kwaad there's a major flaw in your thinking. Attach rate is nowhere's near as important to Nintendo as it is is Microsoft and Sony. Why? The Wii sells at a profit. Nintendo could sell 150m Wiis and no games and still be more profitable than Microsoft will ever be this generation.
Also lower sales of 'real games' is a reality of Nintendo's Blue Ocean strategy. They said from the get-go they would not be pulled into a disasterous fight for core-gamers with the other two (I'm sure Sony in hindsight wished it hadn't either, and Microsoft has openly stated it needs to appeal to more casuals). The Wii is getting more female and mature gamers than any system previously except DS. These owners are not that interested in 'real' games.
That's not bad, there's ample room for both on DS & Wii but the 360 is pure 'core' gamers and it shows in game sales. But look at sales of Nintendogs and Brain Age. Casual gamers DO indeed buy games.
Also, 360 games tend to do gang-busters out the door and drop quickly, were-as Wii games tend to sell fewer at first by have longer, stronger legs. So comparing 1 weeks sales is silly. SMG will consistantly sell well through-out this generation. So will Halo 3 for that matter, I doubt SMG will ever catch it, and I doubt it will ever matter.







